The present invention generally relates to liquid dispensing apparatus and, more specifically, to liquid dispensing manifolds with adjustable slide plates.
Some manufacturing processes involve depositing a liquid, such as an adhesive, onto a substrate, such as a nonwoven web. Typically, the liquid is dispensed from a liquid dispensing apparatus that includes a liquid dispensing module coupled to a liquid manifold which is connected to a source of adhesive. In some manufacturing applications, such as in the manufacture of multilayer diapers, two spaced-apart liquid dispensing modules are coupled to a common liquid manifold, thereby allowing adhesive to be deposited onto the opposing edges of a substrate, such as one layer of the diaper. To ensure proper adhesion between the multiple layers of the diaper, the adhesive must be accurately positioned onto the edges of the various layers making up the diaper. Accordingly, the two liquid dispensing modules must be precisely spaced apart from one another. With prior liquid dispensing apparatus, however, precisely spacing apart the liquid dispensing modules is time consuming and labor intensive.
In prior liquid dispensing apparatus, each of the two liquid dispensing modules couples to respective mounting blocks which are selectively moveable along a slot in the liquid manifold. During the initial set-up of the liquid dispensing apparatus, the location of the mounting blocks along the slot in the liquid manifold is initially estimated so that the liquid is deposited along the edges of the substrate. Once in place, the mounting blocks are secured to the slot by an appropriate fastener, such as a set screw. If the initial location of the liquid dispensing modules is incorrect, thereby dispensing liquid onto the wrong part of the substrate, the liquid dispensing process must be stopped, the fastener holding the mounting blocks must be released, and the mounting blocks manually repositioned along the slot in the liquid manifold. Then the mounting blocks must again be fixedly secured to the slot.
Because the mounting blocks are secured to the slot in the manifold using fasteners such as set screws, the location of the mounting blocks cannot be readily changed during the liquid dispensing process. Instead, if repositioning is required, the entire production line must be shut down, and the liquid dispensing modules be manually repositioned. Manually repositioning the liquid dispensing modules has other drawbacks. For instance, the accuracy with which the liquid dispensing modules can be manually aligned over the substrate varies depending on the technician setting up the liquid dispensing apparatus.
Repositioning and aligning the liquid dispensing modules becomes an even greater issue when the liquid dispensing apparatus is used on a production line capable of fabricating different products having a range of widths. For example, a production line may be used to produce diapers having differing widths to accommodate children of different sizes, e.g., new born, infants, and toddlers. In this situation, the liquid dispensing modules must be manually repositioned each time the diaper style changes in order to accommodate the different widths. Thus, the cumbersome task of repositioning the liquid dispensing modules must be repeated each time the product style, and thus width, changes. Consequently, the down time and expense associated with each product changeover may be significant.
What is needed, therefore, is a liquid dispensing apparatus that permits the liquid dispensing modules to be more precisely positioned so the dispensed liquid engages the desired portion of the substrate. The liquid dispensing apparatus should also provide for repositioning the liquid dispensing modules to significantly reduce the down time of the entire manufacturing process while the alignment process occurs.
The present invention provides a liquid dispensing apparatus that provides for precise adjustment of one or more dispensing modules relative to a substrate. In addition, the liquid dispensing apparatus significantly reduces the time required for systematic adjustment of the dispensing modules. In accordance with the principles of the invention, the liquid dispensing apparatus includes a manifold which has a liquid discharge orifice that is adapted to connect to a source of liquid, such as adhesive. The manifold further has an elongated slot which has a plurality of walls and a recess portion formed in one of those walls. A mounting block has a flange portion that is disposed in and cooperating with the recess portion of the slot so that the mounting block is retained in and selectively slidable along the slot. A dispensing module with a liquid passageway is removably affixed to the mounting block with the liquid passageway in fluid communication with the liquid discharge orifice in the manifold.
The liquid dispensing apparatus may also include a slide plate disposed between the mounting block and the dispensing module. Moreover, the slot in the manifold may include a second recess portion in another of the walls in the slot which is oppositely disposed to the first recess portion. Accordingly, the mounting block has a second flange member disposed in and cooperating with the second recess portion to further retain the mounting block in the slot.
In another embodiment, the liquid dispensing apparatus includes a manifold with a liquid discharge orifice adapted to connect to a source of liquid and a mounting block slidably mounted to the manifold. A dispensing module is removably affixed to the mounting block and has a liquid passage way in fluid communication with the liquid discharge orifice in the manifold. A driven adjustment member is coupled to the mounting block and is selectively operative to slidingly move the mounting block along the manifold. Preferably, the adjustment member includes a threaded rod threadingly coupled to the mounting block.
While the two liquid dispensing apparatus described above include only a single mounting block and dispensing module, it will be appreciated that the liquid dispensing apparatus may include a plurality of dispensing modules mounted respective to a plurality of mounting blocks, each of which is independently movable relative to the manifold.
The invention also contemplates a method for adjusting the location of a dispensing module dispensing liquid onto a substrate where the dispensing module is coupled to a mounting block slidably mounted to a manifold, and a selectively driven adjustment member is coupled to the mounting block. First, the adjustment member is operated so as to slidingly move the mounting block along the manifold such that liquid discharged from the dispensing module contacts the substrate in a predetermined location. After the liquid is discharged in the desired location, the adjustment member is secured so that the mounting block is no longer free to slide along the manifold.
Various additional advantages and features of the invention will become more readily apparent to those of ordinary skill in the art upon review of the following detailed description taken in conjunction with the accompanying drawings.